Lance Armstrong wants to help clean up cycling according to the US Anti-Doping Agency

Lance Armstrong has been given a two-week extension to co-operate with the investigation

The US Anti-Doping Agency has announced Lance Armstrong wants to "assist in the effort to clean up the sport of cycling" and has given the disgraced cyclist a two-week extension to co-operate with investigators.

Armstrong had been given until yesterday to confess all under oath after admitting to doping during each of his seven Tour de France triumphs in a televised interview with Oprah Winfrey last month.

However, USADA has set a new deadline.

Chief executive Travis Tygart said in a statement: "We have been in communication with Mr Armstrong and his representatives and we understand that he does want to be part of the solution and assist in the effort to clean up the sport of cycling.

"We have agreed to his request for an additional two weeks to work on details to hopefully allow for this to happen."

USADA revealed last year that Armstrong had led "the most sophisticated, professionalised and successful doping programme sport has ever seen".

The UCI, cycling's world governing body, stripped Armstrong of his seven Tour titles - none of which were reassigned - and he was banned from sport for life.